Self-concept and self-efficacy are two mechanisms of personal agency that influence adaptive outcomes such as academic performance. With the assumption that these self-beliefs are greatly influenced by processes of social comparison, personal experiences and other significant situational contexts, the study explored the potential differences among students coming from diverse socio-cultural and academic conditions in terms of self-efficacy, self-concept, and performance on a math task. Four groups of Filipino freshman high school students (selective high school in Region 3, n = 66: selective high school in Region 4, n = 69; Filipino - Chinese dominated private high school in NCR, n = 70; and Muslim-dominated public high school in NCR, n = 79), served as data sources. Moreover considering the importance of the level of generality of the assessment of self-concept and self-efficacy, the study looked into the predictive role of these self-beliefs on a Math task specifically on operations involving fractions. Results of a series of ANOVAs revealed that students from the Muslim-dominated group significantly differed across the variables under study, exhibiting lowest levels of self-efficacy, self-concept and performance. Meanwhile, multiple regression showed that self-efficacy, but not self-concept demonstrated predictive utility in terms of test performance. In general, results seem to indicate that indeed, in academic situations, even among diverse groups, there exists a fusion of confidence and competence.